Thermostatic indicator



UNITED STATES PATENT series.

WILLIAM MDRELLI, OF SAN FRANCISJO, GALE. GRNIA, ASSIGNGR OF ONE-HALF TO PHILLIP I). WALSH, OF SAN FRANCISCO, CALIFORNIA.

TKERMOSTATIC INDICATOR.

Specification of Letters Patent.

Application filed August is, 1919. $erial No. 318 550.

To all whom it may concern:

citizen of the United States, and residing in the city and county of San Francisco, State of California, have invented certain new and useful Improvements in Thermostatic Indicators, whereof the following is a specification.

This invention relates to thermostatic indicators, for giving a warning when the ternperature of any desired apparatus reaches a predetermined limit;

consider that my invention will he more particularly useful in connection with the hearings of machinery, and I shall now describe it with reference to that use. It is i" ortant that an instrument for this purp e be extremely sensitive and delicate and it is an object of my invention to produce ining 3. The thermostat i may he set in contactxwith the babbitt, or in a hole drilled therein for the purpose. Should the hearing becbme too warm, the thermostat closes an electric contact, and, an alarm is given. I have shown but one such connection but of course any. number of journals and thei mostats may be connected to one circuit, and an annunciator applied to show from which one the alarm originates.

I will now describe the structure of the thermostatic instrument itself. 5 is a tube, which may he of co per, and which contains an exceedingly no rod or wire 6, ins tened to it at the bottom 7, in any suitable manner, and extending toward the other end i exact terms required by law, and has n 8, containing springs These springs push upward against a disc or piston 10, rich is fastened to the upper end of the ire d, and is held thereby against the push of the spring 9. Upon the top oi the tube, above the disc 10, is a cap 11. closing the tube, and secured by set screws 12. The cap 1.1

is provided with a central insulating hue ing 13, through which is tapped a screw 14, having at its iower end an electric contact point 15. The screw may be adjusted to w any degree and secured by the jam nuts Upon the disc 10 is a metal spring spide: 17. hearing a contact point 18, in registe': with the contact point 15 on the end 0 screw 14. The spring or yielding quality of the spider prevents injury to the delicate contact point from any'excess of action of the devices. A screw ring 19, sore ng down on the inside of the piston 10 retains the spring 17 in place. Electric wires may ii! be connected to the top of screw is as at 20, and to any part of the tube or cap,

at 21. so that a current may ilow when the contacts 15 and 18 touch.

The operation of the instrument is as follows: The wire or rod h is made from a niaterial having a greater co-eflicient of expaifc sion than the tube 5, so that when the tube 5 is heated, its expansion willgneutralize the effect of the heat upon the rod 6, so that as it elongates, the piston 10 is pushed up by the springs 8, and when it is pushed up suiilciently the contacts 15 and will closed, thereby notifying the attendant an undesired increase in temperature of hearing.

Having thus described my invention. an embodiment of it, in the full clear that it comprises a novei. useful and v uahle improvements in the art to which. it pertains, I here state that i do not wish to be limited to the precise construction arrangement of the several parts, as her set forth. as the same may he veriou. U modified by a skilled mechanic without do parting from the spirit of the invention What I claim and desire to secure by Letters Patent of the United States, the following, to wit:

A hearing heat indicator comprising-a tube, a rod connected with said tuise h inga diii'erent thermai coefficient oie'rpan' md,springs to push the sion therefrom, a piston cennected with said In testimony that I claim the foregoing, 1 piston against the have hereto set my hand this 11th day of m1, 2. spi'ing carried by the piston, a ring Aug. 1919, in the presence of two witnesses. 10

ebe" spring when the apparatus is overfor retaining said spring in place and an ad- WILLIAM MORELLI. jusmble ('xmtact screw adapted to bear upon Witnesses:

P. J. WALSH,

iieaisds. F LORENGE L. WOLFE. 

